Harnessing overlapped temperature-salinity gradient in solar-driven interfacial seawater evaporation for efficient steam and electricity generation

Solar-driven interfacial water evaporation(SIWE)offers a superb way to leverage concentrated solar heat to minimize energy dissipation during seawater desalination.It also engenders overlapped temperaturesalinity gradient(TSG)between water-air interface and adjacent seawater,affording opportunities of harnessing electricity.However,the efficiency of conventional SIWE technologies is limited by significant challenges,including salt passivation to hinder evaporation and difficulties in exploiting overlapped TSG simultaneously.Herein,we report self-sustaining hybrid SIWE for not only sustainable seawater desalination but also efficient electricity generation from TSG.It enables spontaneous circulation of salt flux upon seawater evaporation,inducing a self-cleaning evaporative interface without salt passivation for stable steam generation.Meanwhile,this design enables spatial separation and simultaneous utilization of overlapped TSG to enhance electricity generation.These benefits render a remarkable efficiency of90.8%in solar energy utilization,manifesting in co-generation of solar steam at a fast rate of 2.01 kg m^(-2)-h^(-1)and electricity power of 1.91 W m^(-2)with high voltage.Directly interfacing the hybrid SIWE with seawater electrolyzer constructs a system for water-electricity-hydrogen co-generation without external electricity supply.It produces hydrogen at a rapid rate of 1.29 L h^(-1)m^(-2)and freshwater with 22 times lower Na+concentration than the World Health Organization(WHO)threshold.

Promoting and controlling electron transfer of furfural oxidation efficiently harvest electricity,furoic acid,hydrogen gas and hydrogen peroxide

Conventional chemical oxidation of aldehydes such as furfural to corresponding acids by molecular oxygen usually needs high pressure to increase the solubility of oxygen in aqueous phase,while electrochemical oxidation needs input of external electric energy.Herein,we developed a liquid flow fuel cell(LFFC)system to achieve oxidation of furfural in anode for furoic acid production with co-production of hydrogen gas.By controlling the electron transfer in cathode for reduction of oxygen,efficient generation of electricity or production of H_(2)O_(2)were achieved.Metal oxides especially Ag_(2)O have been screened as the efficient catalyst to promote the oxidation of aldehydes,while liquid redox couples were used for promoting the kinetics of oxygen reduction.A novel alkaline-acidic asymmetric design was also used for anolyte and catholyte,respectively,to promote the efficiency of electron transfer.Such an LFFC system achieves efficient conversion of chemical energy of aldehyde oxidation to electric energy and makes full use the transferred electrons for high-value added products without input of external energy.With(VO_(2))_(2)SO_(4)as the electron carrier in catholyte for four-electron reduction of oxygen,the peak output power density(Pmax)at room temperature reached 261 mW/cm^(2)with furoic acid and H_(2)yields of 90%and 0.10 mol/mol furfural,respectively.With anthraquinone-2-sulfonate(AQS)as the cathodic electron carrier,Pmaxof 60 mW/cm^(2)and furoic acid,H_(2)and H_(2)O_(2)yields of 0.88,0.15 and 0.41 mol/mol furfural were achieved,respectively.A new reaction mechanism on furfural oxidation on Ag_(2)O anode was proposed,referring to one-electron and two-electron reaction pathways depending on the fate of adsorbed hydrogen atom transferred from furfural aldehyde group.

Wind Turbine Noise Reduction through Blade Retrofitting

This paper outlines a plan for the effective reduction of the audible sound level produced by aerodynamic noise from the power-generating turbine blades. The contribution of aerodynamic noise can be divided into two categories: inflow turbulence and airfoil self-noise. The base model and retrofit blade designs were modeled in SolidWorks. Subsequently, noise prediction simulations were conducted and compared to the base blade model to determine which modification provided the greatest benefit using SolidWorks Flow Simulation. The result of this project is a series of blade retrofit recommendations that produce a more acoustically efficient design and reduce noise complaints while enabling turbines to be placed in locations that require quieter operations.

Feasible design for electricity generation from Chlorella vulgaris using convenient photosynthetic conditions

Many recent studies are concerned with low cost,easy to handle and alternative renewable energy as a feasible solution for the upcoming crisis of energy shortage.Microalgae are unicellular entities the can only depend on CO_(2),water and solar power to cover their nutritional needs.The current study is concerned with using algal cells in a polymeric hydrogel,as a cheap source of energy for electricity generation.Chlorella vulgaris has been proved to be a promising algal species for electricity generation,as compared with Micractinium reisseri.PVA hydrogel has been used for the immobilization of both algal species in order to protect them from the adverse surrounding conditions in addition to its ability to slowly release the required water molecules according to needs.Under these conditions,C.vulgaris showed the ability to generate 60 mV compared with 15 mV generated by M.reisseri.Scanning electron micrographs showed nano-threads that bind the C.vulgaris cells to each other,indicating the ability of algae to create nanowires that facilitate the electron transfer among algal cells and from cells to the nearest electrode.However,we would expect an increase in the produced potential with simultaneous amendment of environmentally polluted water,such as sewage or waste water.Both of FTIR and raman spectroscopy proved the presence of the characteristic groups of PVA hydrogel and proved the proper integration of the algal cells inside the hydrogel cavities.

Coupling biomass pretreatment for enzymatic hydrolysis and direct biomass-to-electricity conversion with molybdovanadophosphoric heteropolyacids as anode electron transfer carriers

Owing to their acidity,oxidizing ability and redox reversibility,molybdovanadophosphoric heteropolyacids(H_(n+3)PMo_(12-n)VnO40,abbreviated as PMo_(12-n)Vn) were employed as electron transfer carriers for coupling biomass pretreatment for enzymatic hydrolysis and direct biomass-to-electricity conversion.In this novel coupled process,PMo_(12-n)Vn pretreatment that causes deconstruction of cell wall structure with PMo_(12-n)Vn being simultaneously reduced can be considered as the "charging" process.The reduced PMo_(12-n)Vn are further re-oxidized with release of electrons in a liquid flow fuel cell(LFFC) to generate electricity is the "discharging" process.Several Keggin-type PMo_(12-n)Vn with different degree of vanadium substitution(DSV, namely n) were prepared.Compared to Keggin-type phosphomolybdic acid(PMo_(12)),PMo_(12-n)Vn(n=1-6) showed higher oxidizing ability but poorer redox reversibility.The cellulose enzymatic digestibility of PMo_(12-n)Vn pretreated wheat straw generally decreased with increase in DSV, but xylan enzymatic digestibility generally increased with DSV.PMo_(12) pretreatment of wheat straw at 120℃ obtained the highest enzymatic glucan conversion(EGC) reaching 95%,followed by PMo11V1 pretreatment(85%).Discharging of the reduced heteropolyacids in LFFC showed that vanadium substitution could improve the maximum output power density(Pmax).The highest Pmax was obtained by PMo9 V3(44.7 mW/cm^(2)) when FeCl_(3) was used as a cathode electron carrier,while PMo_(12) achieved the lowest Pmax(27.4 mW/cm^(2)).All the heteropolyacids showed good electrode Faraday efficiency(>95%) and cell discharging efficiency(>93%).The energy efficiency of the coupled process based on the heat values of the products and generated electric energy was in the range of 18%-25% depending on DSV.PMo_(12) and PMo11V1 seem to be the most suitable heteropolyacids to mediate the coupled process.

Towards an Ethical and Ecological Approach to Electricity Generation: A Comparative Analysis of Coal and Nuclear Power in the USA

According to the US Energy Information Administration, about 4118 billion kilowatt-hours (kWh) electricity was generated at large-scale generation facilities in 2019. About 63% of this was from fossil fuels, e.g., coal, natural gas, petroleum, and other gases. Environmental exposure to particulates, sulfur dioxide, nitrogen oxides, mercury, arsenic, radioactive fly ash, and other pollutants are extremely detrimental to the human cardiovascular, respiratory, and nervous systems. Such exposure increases the risk of lung cancer, stroke, heart disease, chronic respiratory diseases, respiratory infections, and other illnesses. In light of the challenges associated with renewables providing large quantities of base load power, as well as other factors, the benefits offered by nuclear power should be reexamined by policy makers to move the country towards a more ecological and ethical method of electric power production. This paper offers a concise analysis of many of the salient issues, comparing electricity generation from coal plants and light water nuclear reactors.

Technical Analysis: Generation of Electricity by Pyrolysis of Plastics in a Canadian Environment

The study takes motivation from provincial and national issues regarding waste management and electricity production in Canada.Most sources include previous research relating pyrolysis’applications in different parts of the world.The research included 2-3 weeks of extensive reading of previous research and understanding the theory relating polymers.Research has been conducted to understand why polymers have the properties that they do.Thorough analysis about the chemical reactions relating polymers on a small and large scale is conducted.More research was conducted relating to socio-economic conditions of Canada and Singapore for application purposes.Findings of the research point to an addition the Canadian government can uphold i.e.,build more plastic pyrolysis plants in different regions for waste management.Our findings also suggest that the short term spending on such projects can yield long term benefits.This research is important because it will solve Canada’s non-recyclable waste problems,it will help bring in a new source of electricity and it will help increase the budget of municipalities in the long run.This paper is not just informative on polymers,but also will help readers understand issues regarding Canadian waste management and propose possible solutions.

Electricity generation grew steadily

In the first half of 1996, electricity generation in China had steadily, grown with a total electricity generation accumulated to 508.3 TWh, it was 47.5% of the planned figure in the year, and 8.3% higher than the same period of previous year. Among the generation, hydro-electricity amounted to 78.2 TWh, 5.39% lower than previous year, thermal electricity amounted to 424.55 TWh, 10.87% higher than previous year, nuclear electricity amounted to 5.52 TWh, 47.15% higher than previous year. The steady growth of thermal electricity might attribute to newly installed generating capacity in one hand, and the

Optimal Energy Forecasting Using Hybrid Recurrent Neural Networks

The nation deserves to learn what India’s future energy demand will be in order to plan and implement an energy policy.This energy demand will have to be fulfilled by an adequate mix of existing energy sources,considering the con-straints imposed by future economic and social changes in the direction of a more sustainable world.Forecasting energy demand,on the other hand,is a tricky task because it is influenced by numerous micro-variables.As a result,an macro model with only a few factors that may be predicted globally,rather than a detailed ana-lysis for each of these variables,is required.In this work,a hybrid approach is proposed for identifying the optimal generation-based mix of electricity systems in India.This approach is developed by combing Recalling-Enhanced Recurrent Neural Network(RERNN)and Giza Pyramids Construction(GPC).RERNN pos-sesses selective memory features whereas GPC is a meta-heuristic algorithm that deals with different sets of problems.The goal of this approach is to assess the present load requirements and production profile to understand the current requirement and its production methods.Data on regards to electricity load profile involving the generation of all power plants,capacity factors and transmission limits were gathered from different sources including the Indian National Load Dispatch Centre,Central Electricity Authority database,annual reports of India and regional load dispatching centers.The proposal has introduced the RERNN technique to analyze the optimal time series whereas the GPC technique is involved in the optimization of RERNN parameters.The present work is simu-lated in MATLAB and the performance assessed with different parameters.The present technique gives an effective results in terms of accuracy,computational efficiency and feasibility.

Solar evaporation for simultaneous oil-water separation and electricity generation with Janus wood-based absorbers

Oily wastewater from ocean oil spills endangers marine ecosystems and human health. Therefore, developing an effective and sustainable solution for separating oil-water mixtures is urgent. Interfacial solar photothermal evaporation is a promising approach for the complete separation of two-phase mixtures using only solar energy. Herein, we report a carbonized wood-based absorber with Janus structure of comprising a hydrophobic top-layer and an oleophobic bottom-layer for simultaneous solar-driven oil-water separation and electricity generation. Under sunlight irradiation, the rapid evaporation of seawater will induce a separation of oil-water mixtures, and cause a high salt concentration region underlying the interface, while the bottom “bulk water” maintains in a low salt concentration, thus forming a salinity gradient. Electricity can be generated by salinity gradient power. Therefore, oil-water separation efficiency of > 99% and derived extra electricity power of ~0.1 W/m2 is achieved under solar radiation, demonstrating the feasibility of oil-water separation and electricity production synchronously directly using solar energy. This work provides a green and cost-effective path for the separation of oil-water mixtures.

Performance Analysis of an Efficient Integration System of Coal-Fired Power Plant,Solar Thermal Energy and CO_(2)Capture

Coal-fired power plant is a major contributor to greenhouse gas emissions.The post-combustion capture is a promising method for CO_(2)emission reduction but the high thermal demand is unbearable.To address this issue,solar thermal energy and CO_(2)capture are jointly integrated into the coal-fired power plant in this study.The solar thermal energy is employed to meet the heat requirement of the CO_(2)capture process,thereby avoiding the electricity loss caused by self-driven CO_(2)capture.Furthermore,the heat released from the carbonation reaction of MgO adsorbent is integrated into the steam Rankine cycle.By partially substituting the extracted steam for feedwater heating,the electricity output of the power plant is further increased.According to the results from the developed model,the system could achieve a CO_(2)capture rate of 86.5%and an electricity output enhancement of 9.8%compared to the reference system,which consists of a self-driven CO_(2)capture coal-fired power plant and PV generation unit.The operational strategy is also optimized and the amount of CO_(2)emission reduction on a typical day is increased by 11.06%.This work shows a way to combine fossil fuels and renewable energy for low carbon emissions and efficient power generation.

Effects of crop residues for animal consumption and soil enhancement on the electricity generation potential of residues:A case study of Sawla-Tuna-Kalba district,Ghana

Many studies have estimated the potential of crop residues for energy generation globally and recognized its great potential,especially in rural areas where on-grid electricity is uneconomical.However,crop residues have other equally important uses as animal feed and as mulch for soil enhancement,especially in rural farming communities.Nevertheless,most of the known studies have neglected the estimation of the quantity of crop residues that will be required for feeding animals and also for the enhancement of soil through mulching in their energy potential estimation from crop residues.Neglecting these two important uses can lead to the over-exploitation of the residues for energy generation at the expense of conservation agriculture practices as well as depriving animals of quality feed which can lead to low crop yield and animal production,with the ability to cause hunger and poverty.This study has assessed the potential of electricity generation from agricultural residues in the Sawla-Tuna-Kalba district of Ghana using gasification technology,taking cognizance of the proportion of residues needed for animal consumption and soil enhancement.The results of the study indicate that out of the 207646.22 t of residues that can be generated from maize,yam,cassava,millet,sorghum,and groundnut,26830.36 t(representing 13%)will be required by sheep,goats,and cows for consumption,and 13936.17 t(representing 7%)will be required for mulching soils where the crops are planted.Also,it was found that a total of 592.17 MW∙h of electricity can be generated from crop residues without animal consumption and soil enhancement needs,while 461.89 MW∙h could be generated from the residues,considering animal feed and soil enhancement.This study has indicated that it is not enough to consider soil enhancement and animal feeding in agricultural biomass power generation through recovery factors without the exact quantification of residues required for these purposes since this can lead to a violation of conservation agricultural practice.Hence,it is concluded that the proper estimation of residues required for soil enhancement needs and animal feeding must be considered in the estimation of crop residues available for electricity generation following the method proposed in this study.It is further concluded from this study that,the proper utilization of crop residues serve as an important resource for meeting the electricity demand of the inhabitants in the study location without compromising on the residues that will be required for the consumption of all the animals in the location as well as for enhancement of the soil.

Photon-Assisted Heat Generation by Electric Current in a Quantum Dot Attached to Ferromagnetic Leads

Heat generated by electric current in a quantum dot device contacting a phonon bath is studied using the non- equilibrium Green function technique. Spin-polarized current is generated owing to the Zeeman splitting of the dot level. The current＇s strength and the spin polarization are further manipulated by changing the frequency of an applied photon field and the ferromagnetism on the leads. We find that the associated heat by this spin- polarized current emerges even if the bias voltage is smaller than the phonon energy quanta and obvious negative differential of the heat generation develops when the photon frequency exceeds that of the phonon. It is also found that both the strength and the resonant peaks＇ position of the heat generation can be tuned by changing the value and the arrangement configurations of the magnetic moments of the two leads, and then provides an effective method to generate large spin-polarized current with weak heat. Such a result may be useful in designing low energy consumption spintronic devices.

Proposal of a Solar Thermal Power Plant at Low Temperature Using Solar Thermal Collectors

To this day, only two types of solar power plants have been proposed and built: high temperature thermal solar one and photovoltaic one. It is here proposed a new type of solar thermal plant using glass-top flat surface solar collectors, so working at low temperature (i.e., below 100°C). This power plant is aimed at warm countries, i.e., the ones mainly located between -40° and 40° latitude, having available space along their coast. This land based plant, to install on the seashore, is technologically similar to the one used for OTEC (Ocean Thermal Energy Conversion). This plant, apart from supplying electricity with a much better thermodynamic efficiency than OTEC plants, has the main advantage of providing desalinated water for drinking and irrigation. This plant is designed to generate electricity (and desalinated water) night and day and all year round, by means of hot water storage, with just a variation of the power delivered depending on the season.

Energy Outlook in East Africa Region and the Carbon Emissions for Conventional En-ergy Projection (Part I)

In this investigation, we focus on the current energy sources and future projects situation in East Africa up to 2040. Electricity generation potential of energy mix and electrical capacity will be analyzed. For both electricity generation and electrical capacity, the data source shows that some forms of energies such bio-energy, solar PV, etc. will contribute less as well as with insignificant contribution of nuclear energy. Whereas hydro is dominating comparing with gas, oil, coal, solar PV, bio-energy and other renewables energies. From 2000 up to 2012, hydro and oil were only the one source of electricity generation. Starting from 2020, other forms of energies will appear and continue to increase at different rate. The international trade of electricity in this region will appear in 2020 and continue to increase as predicted by the data. Up to 2040, hydro will play a big role in electricity generation with other renewable energy sources, such as coal, oil, Gas, bio- energy and solar PV that will continue to increase at different rate. The share of solar PV in energy generation will slowly increase compared to other sources. The capacity of hydro and renewable energy sources will be high compared with other sources of energy such as bioenergy, coal, oil, PV solar, and gas. The results show also that bio-energy will increase slowly in electricity generation in comparison with other source of energies. The present report shows that oil will continue to emit a lot carbon dioxide compared to gas and coal. The emission of CO2 from total final consumption (TFC) of oil will continue to be high in comparing with CO2 emission from power generation (PG) of oil. But the emission of carbon dioxide from power generation of coal from 2025 until 2040 will be high compared with emission of CO2 generated from FTC of coal. In this period, the emission from TFC for gas will remain insignificant. The total final consumption emission of oil in general will dominate other emissions from both coal and gas. Due to this high emission of CO2, new technologies should be introduced in order to reduce gas pollution from TFC.